Method and apparatus for random access

ABSTRACT

Various embodiments of the present disclosure provide a method for random access. The method which may be performed by a terminal device comprises determining a interlace configuration for uplink shared channel transmission to a network node in a two-step contention-free random access procedure. The method further comprises performing the uplink shared channel transmission to the network node in the two-step contention-free random access procedure, according to the determined interlace configuration. According to some embodiments of the present disclosure, the interlaced resource allocation for uplink shared channel transmission may be configured for a two-step contention-free random access procedure in a flexible and efficient way, so that the performance of the random access procedure can be improved.

This application is a continuation of U.S. patent application Ser. No.17/797,514, filed Aug. 4, 2022, which is a 35 U.S.C. § 371 nationalphase filing of International Application No. PCT/CN2021/074110, filedJan. 28, 2021, which claims the benefit of International Application No.PCT/CN2020/074528, filed Feb. 7, 2020, the disclosures of which areincorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The present disclosure generally relates to communication networks, andmore specifically, to a method and apparatus for random access.

BACKGROUND

This section introduces aspects that may facilitate a betterunderstanding of the disclosure. Accordingly, the statements of thissection are to be read in this light and are not to be understood asadmissions about what is in the prior art or what is not in the priorart.

Communication service providers and network operators have beencontinually facing challenges to deliver value and convenience toconsumers by, for example, providing compelling network services andperformance. With the rapid development of networking and communicationtechnologies, wireless communication networks such as long-termevolution (LTE) and new radio (NR) networks are expected to achieve hightraffic capacity and end-user data rate with lower latency. In order toconnect to a network node, a random access (RA) procedure may beinitiated for a terminal device. In the RA procedure, system information(SI) and synchronization signals (SS) as well as the related radioresource and transmission configuration can be informed to the terminaldevice by signaling messages from the network node. The RA procedure canenable the terminal device to establish a session for a specific servicewith the network node.

SUMMARY

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

A wireless communication network such as a NR/5G network may be able tosupport flexible network configuration. Different signaling approaches(e.g., a four-step approach, a two-step approach, etc.) may be used fora RA procedure of a terminal device to set up a connection with anetwork node. In the RA procedure, the terminal device may perform a RApreamble transmission and a physical uplink shared channel (PUSCH)transmission to the network node in different messages (e.g., in message1/msg1 and message 3/msg3 for four-step RA, respectively) or in the samemessage (e.g., in message A/msgA for two-step RA). The RA preamble maybe transmitted in a time-frequency physical random access channel(PRACH) occasion (which is also known as a RA occasion, RACH occasion,or RO for short). The PUSCH transmission may occur in a PUSCH occasion(PO) configured with one or more demodulation reference signal (DMRS)resources. The PO may consist of time-frequency radio resourcesallocated for the PUSCH transmission. In some cases, the time-frequencyradio resource allocation may be configured in an interlaced way.Configurations of the interlaced resource allocation for PUSCH may needto be adapted to different RA procedures, e.g. contention-based randomaccess (CBRA) and contention-free random access (CFRA). However, thereis no existing scheme for configuring the interlaced resource allocationfor msgA PUSCH in CFRA. Therefore, it may be desirable to implementconfiguration of the interlaced resource allocation for msgA PUSCH inCFRA efficiently.

Various embodiments of the present disclosure propose a solution for RA,which can enable msgA PUSCH transmission from a terminal device to anetwork node in a CFRA procedure to be configured with interlacedresource allocation, for example, by dedicated signaling and/orutilizing some of existing information, so as to perform configurationof the interlaced resource allocation for msgA PUSCH in the CFRAprocedure in a flexible and efficient way.

It can be appreciated that the terms “four-step RA procedure” and“four-step RACH procedure” mentioned herein may also be referred to asType-1 random access procedure as defined in the 3rd generationpartnership project (3GPP) technical specification (TS) 38.213 V16.0.0,where the entire content of this technical specification is incorporatedinto the present disclosure by reference. These terms may be usedinterchangeably in this document.

Similarly, it can be appreciated that the terms “two-step RA procedure”and “two-step RACH procedure” mentioned herein may also be referred toas Type-2 random access procedure as defined in 3GPP TS 38.213 V16.0.0,and these terms may be used interchangeably in this document.

In addition, it can be appreciated that a two-step CFRA proceduredescribed in this document may refer to a contention-free random accessprocedure in which a terminal device is configured to transmit a msgA toa network node as a first step, and a msgB in response to the msgA isexpected to be received from the network node by the terminal device asa second step. It can be appreciated that the term “two-step CFRA”mentioned herein may also be referred to as “CFRA with two-step RAtype”, and the two terms may be used interchangeably in this document.

It can be realized that the terms “PRACH occasion”, “random accesschannel (RACH) occasion” or “RA occasion” mentioned herein may refer toa time-frequency resource usable for the preamble transmission in a RAprocedure, which may also be referred to as “random access occasion(RO)”. These terms may be used interchangeably in this document.

Similarly, it can be realized that the terms “PUSCH occasion”, “uplinkshared channel occasion” or “shared channel occasion” mentioned hereinmay refer to a time-frequency resource usable for PUSCH transmission ina RA procedure, which may also be referred to as “physical uplink sharedchannel occasion (PO)”. These terms may be used interchangeably in thisdocument.

According to a first aspect of the present disclosure, there is provideda method performed by a terminal device such as a user equipment (UE).The method comprises determining a interlace configuration for uplinkshared channel transmission (e.g., msgA PUSCH transmission, etc.) to anetwork node in a two-step CFRA procedure. In accordance with someexemplary embodiments, the method further comprises performing theuplink shared channel transmission to the network node in the two-stepCFRA procedure, according to the determined interlace configuration.

It can be appreciated that the term “interlace configuration” describedin this document may refer to a configuration which may indicate toenable or disable the interlaced resource allocation and/or indicate howto implement the interlaced resource allocation. In various exemplaryembodiments, the term “interlace configuration” and the term“configuration of the interlaced resource allocation” may be usedinterchangeably.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be based at least in part on dedicatedsignaling for the two-step CFRA procedure from the network node.

In accordance with some exemplary embodiments, the dedicated signalingmay include one or more of:

-   -   a start interlace index for an interlace or a set of interlaces        allocated for the uplink shared channel transmission;    -   a number of consecutive interlaces allocated for the uplink        shared channel transmission; and    -   a dedicated flag indicating whether to enable interlaced        resource allocation for the uplink shared channel transmission        in the two-step CFRA procedure.

In accordance with some exemplary embodiments, the dedicated signalingmay include a specific field with a number of bits to indicate frequencyresource allocation for the uplink shared channel transmission in thetwo-step CFRA procedure.

In accordance with some exemplary embodiments, the number of bits may berelated to a size of an active uplink (UL) bandwidth part (BWP).

In accordance with some exemplary embodiments, the number of bits may bea fixed number.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be based at least in part on commonsignaling from the network node. The common signaling may indicatewhether to enable interlaced resource allocation for the uplink sharedchannel transmission.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be performed by the terminal device based atleast in part on one or more of:

-   -   first configuration information, which may be related to a        interlace configuration for uplink shared channel transmission        of the terminal device in a two-step CBRA procedure; and    -   second configuration information, which may be related to a        interlace configuration for uplink shared channel transmission        of the terminal device with configured grant based scheduling.

In accordance with some exemplary embodiments, the first configurationinformation may be indicated by higher layer signaling (e.g., radioresource control (RRC) signaling, etc.) from the network node.

In accordance with some exemplary embodiments, the first configurationinformation may be predetermined.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be based at least in part on one or more ofthe following messages from the network node:

-   -   a handover command message;    -   a beam failure recover message; and    -   a downlink control channel order for the two-step CFRA        procedure.

According to a second aspect of the present disclosure, there isprovided an apparatus which may be implemented as a terminal device. Theapparatus comprises one or more processors and one or more memoriescomprising computer program codes. The one or more memories and thecomputer program codes are configured to, with the one or moreprocessors, cause the apparatus at least to perform any step of themethod according to the first aspect of the present disclosure.

According to a third aspect of the present disclosure, there is provideda computer-readable medium having computer program codes embodiedthereon which, when executed on a computer, cause the computer toperform any step of the method according to the first aspect of thepresent disclosure.

According to a fourth aspect of the present disclosure, there isprovided an apparatus which may be implemented as a terminal device. Theapparatus comprises a determining unit and a performing unit. Inaccordance with some exemplary embodiments, the determining unit isoperable to carry out at least the determining step of the methodaccording to the first aspect of the present disclosure. The performingunit is operable to carry out at least the performing step of the methodaccording to the first aspect of the present disclosure. In anembodiment, the performing unit may be implemented as a transmittingunit to carry out at least the step of performing the uplink sharedchannel transmission in the method according to the first aspect of thepresent disclosure.

According to a fifth aspect of the present disclosure, there is provideda method performed by a network node such as a base station. The methodcomprises determining a interlace configuration for uplink sharedchannel transmission of a terminal device in a two-step CFRA procedure.In accordance with some exemplary embodiments, the method furthercomprises receiving the uplink shared channel transmission from theterminal device in the two-step CFRA procedure, according to thedetermined interlace configuration.

In accordance with some exemplary embodiments, the interlaceconfiguration for uplink shared channel transmission according to thefifth aspect of the present disclosure may correspond to the interlaceconfiguration for uplink shared channel transmission according to thefirst aspect of the present disclosure. Thus, the interlaceconfiguration for uplink shared channel transmission according to thefirst and fifth aspects of the present disclosure may have the same orsimilar contents and/or feature elements.

In accordance with some exemplary embodiments, the method according tothe fifth aspect of the present disclosure may further comprise:transmitting dedicated signaling to the terminal device to indicate thedetermined interlace configuration.

In accordance with some exemplary embodiments, the dedicated signalingaccording to the fifth aspect of the present disclosure may correspondto the dedicated signaling according to the first aspect of the presentdisclosure, and thus may have the same or similar contents and/orfeature elements.

In accordance with some exemplary embodiments, the method according tothe fifth aspect of the present disclosure may further comprise:transmitting common signaling to the terminal device to indicate whetherto enable interlaced resource allocation for the uplink shared channeltransmission.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be performed by the network node based atleast in part on first configuration information related to CBRAconfiguration (e.g., the first configuration information according tothe first aspect of the present disclosure) and/or second configurationinformation related to configured grant based scheduling (e.g., thesecond configuration information according to the first aspect of thepresent disclosure).

In accordance with some exemplary embodiments, the method according tothe fifth aspect of the present disclosure may further comprise:transmitting higher layer signaling (e.g., RRC signaling, etc.) to theterminal device to indicate the first configuration information. It canbe appreciated that the first configuration information may bepredetermined.

In accordance with some exemplary embodiments, the method according tothe fifth aspect of the present disclosure may further comprise:indicating the determined interlace configuration to the terminal devicein one or more of the following messages:

-   -   a handover command message;    -   a beam failure recover message; and    -   a downlink control channel order for the two-step CFRA        procedure.

According to a sixth aspect of the present disclosure, there is providedan apparatus which may be implemented as a network node. The apparatuscomprises one or more processors and one or more memories comprisingcomputer program codes. The one or more memories and the computerprogram codes are configured to, with the one or more processors, causethe apparatus at least to perform any step of the method according tothe fifth aspect of the present disclosure.

According to a seventh aspect of the present disclosure, there isprovided a computer-readable medium having computer program codesembodied thereon which, when executed on a computer, cause the computerto perform any step of the method according to the fifth aspect of thepresent disclosure.

According to an eighth aspect of the present disclosure, there isprovided an apparatus which may be implemented as a network node. Theapparatus comprises a determining unit and a receiving unit. Inaccordance with some exemplary embodiments, the determining unit isoperable to carry out at least the determining step of the methodaccording to the fifth aspect of the present disclosure. The receivingunit is operable to carry out at least the receiving step of the methodaccording to the fifth aspect of the present disclosure.

According to a ninth aspect of the present disclosure, there is provideda method implemented in a communication system which may include a hostcomputer, a base station and a UE. The method may comprise providinguser data at the host computer. Optionally, the method may comprise, atthe host computer, initiating a transmission carrying the user data tothe UE via a cellular network comprising the base station which mayperform any step of the method according to the fifth aspect of thepresent disclosure.

According to a tenth aspect of the present disclosure, there is provideda communication system including a host computer. The host computer maycomprise processing circuitry configured to provide user data, and acommunication interface configured to forward the user data to acellular network for transmission to a UE. The cellular network maycomprise a base station having a radio interface and processingcircuitry. The base station's processing circuitry may be configured toperform any step of the method according to the fifth aspect of thepresent disclosure.

According to an eleventh aspect of the present disclosure, there isprovided a method implemented in a communication system which mayinclude a host computer, a base station and a UE. The method maycomprise providing user data at the host computer. Optionally, themethod may comprise, at the host computer, initiating a transmissioncarrying the user data to the UE via a cellular network comprising thebase station. The UE may perform any step of the method according to thefirst aspect of the present disclosure.

According to a twelfth aspect of the present disclosure, there isprovided a communication system including a host computer. The hostcomputer may comprise processing circuitry configured to provide userdata, and a communication interface configured to forward user data to acellular network for transmission to a UE. The UE may comprise a radiointerface and processing circuitry. The UE's processing circuitry may beconfigured to perform any step of the method according to the firstaspect of the present disclosure.

According to a thirteenth aspect of the present disclosure, there isprovided a method implemented in a communication system which mayinclude a host computer, a base station and a UE. The method maycomprise, at the host computer, receiving user data transmitted to thebase station from the UE which may perform any step of the methodaccording to the first aspect of the present disclosure.

According to a fourteenth aspect of the present disclosure, there isprovided a communication system including a host computer. The hostcomputer may comprise a communication interface configured to receiveuser data originating from a transmission from a UE to a base station.The UE may comprise a radio interface and processing circuitry. The UE'sprocessing circuitry may be configured to perform any step of the methodaccording to the first aspect of the present disclosure.

According to a fifteenth aspect of the present disclosure, there isprovided a method implemented in a communication system which mayinclude a host computer, a base station and a UE. The method maycomprise, at the host computer, receiving, from the base station, userdata originating from a transmission which the base station has receivedfrom the UE. The base station may perform any step of the methodaccording to the fifth aspect of the present disclosure.

According to a sixteenth aspect of the present disclosure, there isprovided a communication system which may include a host computer. Thehost computer may comprise a communication interface configured toreceive user data originating from a transmission from a UE to a basestation. The base station may comprise a radio interface and processingcircuitry. The base station's processing circuitry may be configured toperform any step of the method according to the fifth aspect of thepresent disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure itself, the preferable mode of use and further objectivesare best understood by reference to the following detailed descriptionof the embodiments when read in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a diagram illustrating an exemplary four-step RA procedureaccording to an embodiment of the present disclosure;

FIG. 2A is a diagram illustrating an exemplary two-step RA procedureaccording to an embodiment of the present disclosure;

FIG. 2B is a diagram illustrating exemplary CFRA with two-step RA typeaccording to an embodiment of the present disclosure;

FIG. 3 is a flowchart illustrating a method according to someembodiments of the present disclosure;

FIG. 4 is a flowchart illustrating another method according to someembodiments of the present disclosure;

FIG. 5 is a block diagram illustrating an apparatus according to someembodiments of the present disclosure;

FIG. 6A is a block diagram illustrating another apparatus according tosome embodiments of the present disclosure;

FIG. 6B is a block diagram illustrating a further apparatus according tosome embodiments of the present disclosure;

FIG. 7 is a block diagram illustrating a telecommunication networkconnected via an intermediate network to a host computer in accordancewith some embodiments of the present disclosure;

FIG. 8 is a block diagram illustrating a host computer communicating viaa base station with a UE over a partially wireless connection inaccordance with some embodiments of the present disclosure;

FIG. 9 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure;

FIG. 10 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure;

FIG. 11 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure; and

FIG. 12 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment of the presentdisclosure.

DETAILED DESCRIPTION

The embodiments of the present disclosure are described in detail withreference to the accompanying drawings. It should be understood thatthese embodiments are discussed only for the purpose of enabling thoseskilled persons in the art to better understand and thus implement thepresent disclosure, rather than suggesting any limitations on the scopeof the present disclosure. Reference throughout this specification tofeatures, advantages, or similar language does not imply that all of thefeatures and advantages that may be realized with the present disclosureshould be or are in any single embodiment of the disclosure. Rather,language referring to the features and advantages is understood to meanthat a specific feature, advantage, or characteristic described inconnection with an embodiment is included in at least one embodiment ofthe present disclosure. Furthermore, the described features, advantages,and characteristics of the disclosure may be combined in any suitablemanner in one or more embodiments. One skilled in the relevant art willrecognize that the disclosure may be practiced without one or more ofthe specific features or advantages of a particular embodiment. In otherinstances, additional features and advantages may be recognized incertain embodiments that may not be present in all embodiments of thedisclosure.

As used herein, the term “communication network” refers to a networkfollowing any suitable communication standards, such as new radio (NR),long term evolution (LTE), LTE-Advanced, wideband code division multipleaccess (WCDMA), high-speed packet access (HSPA), and so on. Furthermore,the communications between a terminal device and a network node in thecommunication network may be performed according to any suitablegeneration communication protocols, including, but not limited to, thefirst generation (1G), the second generation (2G), 2.5G, 2.75G, thethird generation (3G), 4G, 4.5G, 5G communication protocols, and/or anyother protocols either currently known or to be developed in the future.

The term “network node” refers to a network device in a communicationnetwork via which a terminal device accesses to the network and receivesservices therefrom. The network node may refer to a base station (BS),an access point (AP), a multi-cell/multicast coordination entity (MCE),a controller or any other suitable device in a wireless communicationnetwork. The BS may be, for example, a node B (NodeB or NB), an evolvedNodeB (eNodeB or eNB), a next generation NodeB (gNodeB or gNB), a remoteradio unit (RRU), a radio header (RH), a remote radio head (RRH), arelay, a low power node such as a femto, a pico, and so forth.

Yet further examples of the network node comprise multi-standard radio(MSR) radio equipment such as MSR BSs, network controllers such as radionetwork controllers (RNCs) or base station controllers (BSCs), basetransceiver stations (BTSs), transmission points, transmission nodes,positioning nodes and/or the like. More generally, however, the networknode may represent any suitable device (or group of devices) capable,configured, arranged, and/or operable to enable and/or provide aterminal device access to a wireless communication network or to providesome service to a terminal device that has accessed to the wirelesscommunication network.

The term “terminal device” refers to any end device that can access acommunication network and receive services therefrom. By way of exampleand not limitation, the terminal device may refer to a mobile terminal,a user equipment (UE), or other suitable devices. The UE may be, forexample, a subscriber station, a portable subscriber station, a mobilestation (MS) or an access terminal (AT). The terminal device mayinclude, but not limited to, portable computers, image capture terminaldevices such as digital cameras, gaming terminal devices, music storageand playback appliances, a mobile phone, a cellular phone, a smartphone, a tablet, a wearable device, a personal digital assistant (PDA),a vehicle, and the like.

As yet another specific example, in an Internet of things (IoT)scenario, a terminal device may also be called an IoT device andrepresent a machine or other device that performs monitoring, sensingand/or measurements etc., and transmits the results of such monitoring,sensing and/or measurements etc. to another terminal device and/or anetwork equipment. The terminal device may in this case be amachine-to-machine (M2M) device, which may in a 3rd generationpartnership project (3GPP) context be referred to as a machine-typecommunication (MTC) device.

As one particular example, the terminal device may be a UE implementingthe 3GPP narrow band Internet of things (NB-IoT) standard. Particularexamples of such machines or devices are sensors, metering devices suchas power meters, industrial machinery, or home or personal appliances,e.g. refrigerators, televisions, personal wearables such as watches etc.In other scenarios, a terminal device may represent a vehicle or otherequipment, for example, a medical instrument that is capable ofmonitoring, sensing and/or reporting etc. on its operational status orother functions associated with its operation.

As used herein, the terms “first”, “second” and so forth refer todifferent elements. The singular forms “a” and “an” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises”, “comprising”, “has”, “having”,“includes” and/or “including” as used herein, specify the presence ofstated features, elements, and/or components and the like, but do notpreclude the presence or addition of one or more other features,elements, components and/or combinations thereof. The term “based on” isto be read as “based at least in part on”. The term “one embodiment” and“an embodiment” are to be read as “at least one embodiment”. The term“another embodiment” is to be read as “at least one other embodiment”.Other definitions, explicit and implicit, may be included below.

Wireless communication networks are widely deployed to provide varioustelecommunication services such as voice, video, data, messaging andbroadcasts. As described previously, in order to connect to a networknode such as a gNB in a wireless communication network, a terminaldevice such as a UE may need to perform a RA procedure to exchangeessential information and messages for communication link establishmentwith the network node.

FIG. 1 is a diagram illustrating an exemplary four-step RA procedureaccording to an embodiment of the present disclosure. As shown in FIG. 1, a UE can detect a synchronization signal (SS) by receiving 101 an SSB(e.g., a primary synchronization signal (PSS), a secondarysynchronization signal (SSS), and physical broadcast channel (PBCH))from a gNB in a NR system. The UE can decode 102 some system information(e.g., remaining minimum system information (RMSI) and other systeminformation (OSI)) broadcasted in the downlink (DL). Then the UE cantransmit 103 a PRACH preamble (message 1/msg1) in the uplink (UL). ThegNB can reply 104 with a random access response (RAR, message 2/msg2).In response to the RAR, the UE can transmit 105 the UE's identificationinformation (message 3/msg3) on PUSCH. Then the gNB can send 106 acontention resolution message (CRM, message 4/msg4) to the UE.

In the exemplary procedure, the UE transmits message 3/msg3 on PUSCHafter receiving a timing advance command in the RAR, allowing message3/msg3 on PUSCH to be received with timing accuracy within a cyclicprefix (CP). Without this timing advance, a very large CP may be neededin order to be able to demodulate and detect message3/msg3 on PUSCH,unless the communication system is applied in a cell with very smalldistance between the UE and the gNB. Since the NR system can alsosupport larger cells with a need for providing a timing advance commandto the UE, the four-step approach is needed for the RA procedure.

FIG. 2A is a diagram illustrating an exemplary two-step RA procedureaccording to an embodiment of the present disclosure. Similar to theprocedure as shown in FIG. 1 , in the procedure shown in FIG. 2A, a UEcan detect a SS by receiving 201 an SSB (e.g., comprising a PSS, a SSSand PBCH) from a gNB in a NR system, and decode 202 system information(e.g., RMSI and OSI) broadcasted in the DL. Compared to the four-stepapproach as shown in FIG. 1 , the UE performing the procedure in FIG. 2Acan complete random access in only two steps. Firstly, the UE sends 203a/203 b to the gNB a message A (msgA) including RA preamble togetherwith higher layer data such as a radio resource control (RRC) connectionrequest possibly with some payload on PUSCH. Secondly, the gNB sends 204to the UE a RAR (also called message B or msgB) including UE identifierassignment, timing advance information, a contention resolution message,and etc. It can be seen that there may be no explicit grant from msgBfor PUSCH in msgA as the msgB is after msgA.

In the two-step RA procedure, the preamble and msgA PUSCH can betransmitted by the UE in one message called message A. For transmissionof msgA PUSCH, i.e. the PUSCH part of msgA, the notion of a PUSCHresource unit may be introduced, where a PUSCH resource unit may consistof time-frequency radio resources of transmission and DMRS sequenceconfiguration. Two simultaneous msgA PUSCH transmissions can bedistinguished by the receiver according to different PUSCH resourceunits used for the two msgA PUSCH transmissions. The notion of PUSCHoccasion also may be introduced, where a PUSCH occasion may consist oftime-frequency radio resources for the transmission of msgA PUSCH.

In accordance with some exemplary embodiments, a RA procedure such astwo-step RACH and four-step RACH can be performed in two different ways,e.g., contention-based (CBRA) and contention-free (CFRA). The differenceis in that which preamble is used. In the contention-based case, a UEmay randomly select a preamble from a range of preambles. For this case,there may be a collision if two UEs select the same preamble. In thecontention-free case, a UE may be given a specific preamble by thenetwork, which ensures that two UEs will not select the same preamble,thus the RA is collision-free. The CBRA may be typically used when a UEis in an idle/inactive state and wants to go to the connected state,while the CFRA may be used for performing handover and/or in beamfailure procedures.

FIG. 2B is a diagram illustrating exemplary CFRA with two-step RA typeaccording to an embodiment of the present disclosure. The procedureillustrated in FIG. 2B may also be referred to as a two-step CFRAprocedure. As shown in FIG. 2B, in the case of CFRA with two-step RAtype, a UE may receive a RA preamble and PUSCH assignment from a gNB instep 0, prior to transmitting msgA (including RA preamble and PUSCHpayload) to the gNB in step A and receiving msgB (RAR) from the gNB instep B.

In accordance with some exemplary embodiments, interlaced resourceallocation may be configured for communications between a network nodeand a terminal device. As described in 3GPP TS 38.211 V16.0.0, where theentire content of this technical specification is incorporated into thepresent disclosure by reference, interlaced resource blocks may bedefined depending on the subcarrier spacing (SCS) μ configured for anactive UL bandwidth part (BWP). As an example, multiple orthogonalfrequency division multiplex (OFDM) numerologies may be supported asgiven by Table 1, where Δf indicates SCS in kHz, μ and the cyclic prefixfor a BWP may be obtained from the higher-layer parametersubcarrierSpacing and cyclicPrefix, respectively.

TABLE 1 μ Δf = 2^(μ) · 15[kHz] Cyclic prefix 0 15 Normal 1 30 Normal 260 Normal, Extended 3 120 Normal 4 240 Normal

In accordance with an exemplary embodiment, multiple interlaces ofresource blocks may be defined as described in 3GPP TS 38.211 V16.0.0,where interlace m∈{0, 1, . . . , M−1} consists of common resource blocks{m, M+m, 2M+m, 3M+m, . . . }, with M being the number of interlacesgiven by Table 2.

TABLE 2 μ M 0 10 1 5

Table 2 shows the number of resource block interlaces M corresponding toparameter μ, where μ=0 means 15 kHz SCS and μ=1 means 30 kHz SCS.

The relation between the interlaced resource block n_(IRB,m) ^(μ)∈{0, 1,. . . } in BWP i and interlace m and the common resource block n_(CRB)^(μ) may be given by the following formula:

n _(CRB) ^(μ) =Mn _(IRB,m) ^(μ) +N _(BWP,i) ^(start,μ)+((m−N _(BWP,i)^(start,μ))mod M)  (1)

where N_(BWP,i) ^(start,μ) is the common resource block where the BWPstarts relative to common resource block 0. If there is no risk forconfusion, the index μ may be dropped.

In accordance with some exemplary embodiments, interlaced resourceallocation may be configured for msg3 transmission and normal PUSCHtransmission (e.g., dynamic grant scheduled PUSCH). For msg3 and normalPUSCH, the useInterlacePUSCH-Common parameter may be used to determinewhether the frequency domain resource allocation is configured in aninterlaced way or not, so as to determine whether to implementinterlaced msg3 PUSCH and interlaced normal PUSCH. In the case that thisparameter is provided, UL resource allocation type 2 as described insection 6.1.2.2.3 in 3GPP TS 38.214 V16.0.0 may be applied, where theentire content of this technical specification is incorporated into thepresent disclosure by reference.

According to an exemplary embodiment for msg3, a 12-bit field in RAR maybe provided for the interlaced frequency domain resource allocation. Theexemplary RAR grant content field size is given in Table 3.

TABLE 3 RAR grant field Number of bits Frequency hopping flag 1 PUSCHfrequency 14, for operation without shared spectrum channel accessresource allocation 12, for operation with shared spectrum channelaccess PUSCH time 4 resource allocation MCS 4 TPC command for PUSCH 3CSI request 1 ChannelAccess-CPext 0, for operation without sharedspectrum channel access 2, for operation with shared spectrum channelaccess

As shown in Table 3, the 12-bit field “PUSCH frequency resourceallocation” may be used for operation with shared spectrum channelaccess (e.g., unlicensed band, etc.).

For normal PUSCH dynamically scheduled by downlink control information(DCI), ┌log₂(N_(RB) ^(UL,BWP)(N_(RB) ^(UL,BWP)+1)/2)┐ bits may providethe frequency domain resource allocation as described in section6.1.2.2.2 of 3GPP TS 38.214 V16.0.0, where N_(RB) ^(UL,BWP) is the sizeof the initial or active UL BWP.

In accordance with an exemplary embodiment for msgA PUSCH in a two-stepCBRA procedure, the interlaced msgA PUSCH may be configured per msgAPUSCH configuration per BWP as described in section 8.1A of 3GPP TS38.213 V16.0.0. For example, a UE may determine a first interlace orfirst resource block (RB) for a first PUSCH occasion in an active UL BWPrespectively from the parameter interlaceIndexFirstPOMsgAPUSCH or fromthe parameter frequencyStartMsgAPUSCH that provides an offset, in numberof RBs in the active UL BWP, from a first RB of the active UL BWP. APUSCH occasion may include a number of interlaces or a number of RBsprovided by the parameter nrofInterlacesPerMsgAPO or by the parameternrofPRBsperMsgAPO, respectively.

As described with respect to FIG. 2A and FIG. 2B, in a two-step RAprocedure, the preamble and msgA PUSCH may be transmitted by a UE in onemessage called message A. In accordance with an exemplary embodiment,the msgA PUSCH resource allocation for CFRA may be defined in dedicatedsignaling. For example, the PUSCH resource for two-step CFRA associatedwith the dedicated preamble may be configured to a UE via the dedicatedsignaling. In this case, the msgA PUSCH resource allocation for CFRA maynot be included in system information block type 1 (SIB1).

Various exemplary embodiments of the present disclosure propose asolution for RA, which can enable the interlaced msgA PUSCH in atwo-step CFRA procedure. According to the proposed solution, theinterlaced resource allocation may be configured for msgA PUSCHtransmission in CFRA. In accordance with some exemplary embodiments, theconfiguration of interlaced resource allocation for msgA PUSCHtransmission in CFRA may be provided at least partly by dedicatedsignaling. Alternatively or additionally, the configuration ofinterlaced resource allocation for msgA PUSCH transmission in CFRA maybe provided at least partly by common signaling for the interlaced PUSCHresource. In accordance with some exemplary embodiments, some ofexisting signaling or parameters for interlaced resource configurationmay be utilized or reused to configure the interlaced resourceallocation for msgA PUSCH transmission in CFRA. In this way, theconfiguration of interlaced msgA PUSCH in the two-step CFRA proceduremay be performed with enhanced resource utilization and improvedtransmission efficiency and flexibility.

In accordance with some exemplary embodiments, at least part ofconfiguration of interlaced msgA PUSCH (also called “the interlaced msgAPUSCH configuration”, or “interlace configuration” for short) may beprovided in the dedicated signaling for a two-step CFRA procedure.According to an exemplary embodiment, the interlace configuration may beexplicitly provided by one or more of the following elements in thededicated signaling:

-   -   the start interlace index for an interlace or a set of        interlaces allocated for the PUSCH transmission (e.g., the start        interlace index for the first interlace allocated for the PUSCH        transmission);    -   the number of consecutive interlaces allocated for the msgA        PUSCH transmission; and    -   the dedicated interlace on-off flag (e.g., using a specific        parameter such as useInterlaceMsgAPUSCH-Dedicated, if this        parameter is provided and/or set to a first value such as “1”,        the interlaced msgA PUSCH resource allocation is enabled; and if        this parameter is set to a second value such as “0” or the        parameter is not provided, non-interlaced msgA PUSCH resource        allocation is used).

In accordance with some exemplary embodiments, the common interlaceenabling signaling (e.g. the existing signalinguseInterlacePUSCH-Common, etc.) may be utilized or reused to indicate atleast part of the configuration of interlaced msgA PUSCH. As an example,two parameters interlaceIndexFirst InterlaceMsgAPUSCHCFRA andnrofInterlacesMsgAPUSCHCFRA as shown in Table 4 may be provided in aspecific information element (IE) such as RACH-ConfigDedicated IE forthe interlace configuration of msgA PUSCH, in the case that thesignaling useInterlacePUSCH-Common is provided.

TABLE 4 Parameter Description ValueinterlaceIndexFirstInterlaceMsgAPUSCHCFRA Interlace index of the INTEGERfirst interlace for the {1 . . . 10} for msgA PUSCH in frequency 15 kHzSCS, domain if interlaced msgA INTEGER PUSCH in CFRA is enabled. {1 . .. 5} for 30 kHz SCS nrofInterlacesMsgAPUSCHCFRA Number of consecutiveINTEGER interlaces of the msgA {1 . . . 10} for PUSCH if interlaced 15kHz SCS, msgA PUSCH in CFRA INTEGER is enabled. {1 . . . 5} for 30 kHzSCS

In accordance with some exemplary embodiments, the dedicated interlaceon-off flag (e.g., useInterlaceMsgAPUSCH-Dedicated, etc.) may be used tooverride the common interlace enabling flag (e.g.,useInterlacePUSCH-Common, etc.). For example, if the dedicated interlaceon-off flag indicates to enable the interlace configuration of msgAPUSCH for a specific UE, then the interlaced msgA PUSCH resourceallocation may be implemented for this UE, regardless of whether thecommon interlace enabling flag indicates to enable or disable theinterlace configuration. In the case that the dedicated interlace on-offflag for the UE indicates to disable the interlace configuration of msgAPUSCH, then the interlaced msgA PUSCH resource allocation may not beapplied for the UE, even though the common interlace enabling flagindicates to enable the interlace configuration.

In accordance with some exemplary embodiments, the interlaceconfiguration may be determined by a number of bits for frequency domainresource allocation, e.g., in the dedicated signaling or other suitablesignaling/messages. According to an exemplary embodiment, the number ofbits may be used to determine the frequency domain resource allocationof msgA PUSCH in two-step CFRA in the case that the interlaced PUSCH isenabled, according to the procedure as described in section 6.1.2.2.3 in3GPP TS 38.214 V16.0.0. In an embodiment, the “number of bits” may berelated to at least the active UL BWP size. In another embodiment, the“number of bits” may be a fixed number, e.g. 12 bits.

According to an exemplary embodiment, a specific field such as┌log₂(N_(RB) ^(UL,BWP)(N_(RB) ^(UL,BWP)+1)/2)┐ bit-field “PUSCHfrequency resource allocation” may be provided in an IE (e.g.,RACH-ConfigDedicated or other proper IEs in the dedicated signaling) forthe interlace configuration of msgA PUSCH, in the case thatuseInterlacePUSCH-Common is provided to enable the interlaced PUSCH,where N_(RB) ^(UL,BWP) is the size of the initial or active UL BWP. Thespecific field may be used to determine the frequency domain resourceallocation of msgA PUSCH in two-step CFRA, for example, according to theprocedure described in section 6.1.2.2.3 in 3GPP TS 38.214 V16.0.0.

In accordance with some exemplary embodiments, the interlaced msgA PUSCHconfiguration for CFRA may be implemented by utilizing or reusing one ofthe interlace configurations of msgA PUSCH for CBRA. In an exemplaryembodiment, first configuration information related to the reusedinterlace configuration of msgA PUSCH for CBRA may indicate which one ofthe interlace configurations of msgA PUSCH for CBRA may be selected formsgA PUSCH in CFRA. Alternatively or additionally, the firstconfiguration information may indicate which PO in the set of POsconfigured for msgA PUSCH in CBRA may be selected for msgA PUSCH in theCFRA. In this way, one PO may be selected for CFRA configuration fromone msgA PUSCH configuration for CBRA that is selected from a set ofmsgA PUSCH configurations in the active BWP, in the case that theinterlaced PUSCH is configured. It can be appreciated that the firstconfiguration information may be predetermined or RRC configured.

In accordance with some exemplary embodiments, the interlaced msgA PUSCHconfiguration for CFRA may be implemented by utilizing or reusing theinterlace configuration provided for PUSCH transmission with configuredgrant based scheduling. According to an exemplary embodiment, theinterlaced msgA PUSCH configuration for CFRA may utilize or reuse one ormore of the following parameters as described in section 6.1.2.3 of 3GPPTS 38.214 V16.0.0 for the case of configured UL grant Type 1:

-   -   the parameter useInterlacePUSCH-Dedicated used for configured        grant type 1 PUSCH transmission; and    -   the parameter “frequency domain resource allocation”.

As described in section 10.3 of 3GPP TS 38.300 V15.7.0, where the entirecontent of this technical specification is incorporated into the presentdisclosure by reference, the following two types of configured UL grantsmay be defined for configured grant scheduled PUSCH in a NR system:

-   -   With Type 1, RRC directly provides the configured UL grant        (including the periodicity).    -   With Type 2, RRC defines the periodicity of the configured UL        grant while physical downlink control channel (PDCCH) addressed        to configured scheduling-radio network temporary identifier        (CS-RNTI) can either signal and activate the configured UL grant        (e.g., as described in section 5.8.2 of 3GPP TS 38.321 V15.7.0,        where the entire content of this technical specification is        incorporated into the present disclosure by reference), or        deactivate it; i.e. a PDCCH addressed to CS-RNTI indicates that        the UL grant can be implicitly reused according to the        periodicity defined by RRC, until deactivated.

In accordance with some exemplary embodiments, the interlaced msgA PUSCHconfiguration for CFRA may be provided in a handover command message, abeam failure recover message, a PDCCH order which may be related to therandom access with two-step CFRA, and/or any other possiblesignaling/messages (e.g., various physical layer signaling, higher layersignaling such as RRC signaling, etc.).

It can be realized that signaling, messages, parameters, variables andsettings related to the interlace configuration for msgA PUSCH in CFRAdescribed herein are just examples. Other suitable signalingtransmissions, parameter settings, the associated configurations and thespecific values thereof may also be applicable to implement the proposedmethods.

It is noted that some embodiments of the present disclosure are mainlydescribed in relation to 5G or NR specifications being used asnon-limiting examples for certain exemplary network configurations andsystem deployments. As such, the description of exemplary embodimentsgiven herein specifically refers to terminology which is directlyrelated thereto. Such terminology is only used in the context of thepresented non-limiting examples and embodiments, and does naturally notlimit the present disclosure in any way. Rather, any other systemconfiguration or radio technologies may equally be utilized as long asexemplary embodiments described herein are applicable.

FIG. 3 is a flowchart illustrating a method 300 according to someembodiments of the present disclosure. The method 300 illustrated inFIG. 3 may be performed by a terminal device or an apparatuscommunicatively coupled to the terminal device. In accordance with anexemplary embodiment, the terminal device such as a UE may be configuredto connect to a network node such as a gNB, for example, by performing aRA procedure (e.g., a two-step CFRA procedure).

According to the exemplary method 300 illustrated in FIG. 3 , theterminal device may determine a interlace configuration for uplinkshared channel transmission to a network node in a two-step CFRAprocedure, as shown in block 302. The uplink shared channel transmissionmay comprise msgA PUSCH transmission from the terminal device to thenetwork node. In accordance with some exemplary embodiments, theinterlace configuration may indicate to enable or disable interlacedresource allocation for the uplink shared channel transmission from theterminal device to the network node in the two-step CFRA procedure. Theinterlace configuration may also indicate how to implement theinterlaced resource allocation for the uplink shared channeltransmission of the terminal device. According to the determinedinterlace configuration, the terminal device may perform the uplinkshared channel transmission to the network node in the two-step CFRAprocedure, as shown in block 304.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be performed by the terminal device based atleast in part on dedicated signaling (e.g., RACH-ConfigDedicated, etc.)for the two-step CFRA procedure from the network node.

In accordance with some exemplary embodiments, the dedicated signalingmay include one or more of:

-   -   a start interlace index for an interlace or a set of interlaces        allocated for the uplink shared channel transmission (e.g., a        specific parameter such as        interlaceIndexFirstInterlaceMsgAPUSCHCFRA, etc.);    -   a number of consecutive interlaces allocated for the uplink        shared channel transmission (e.g., another specific parameter        such as nrofInterlacesMsgAPUSCHCFRA, etc.); and    -   a dedicated flag indicating whether to enable interlaced        resource allocation for the uplink shared channel transmission        in the two-step CFRA procedure (e.g., the dedicated interlace        on-off flag useInterlaceMsgAPUSCH-Dedicated, etc.).

It can be appreciated that the dedicated flag may also be used toindicate whether to disable the interlaced resource allocation for theuplink shared channel transmission in the two-step CFRA procedure.

In accordance with some exemplary embodiments, the dedicated signalingmay include a specific field with a number of bits to indicate frequencyresource allocation for the uplink shared channel transmission in thetwo-step CFRA procedure. According to an exemplary embodiment, thenumber of bits may be related to the size of an initial or active ULBWP. For example, the specific field may be a ┌log₂(N_(RB)^(UL,BWP)(N_(RB) ^(UL,BWP)+1)/2)┐ bit-field “PUSCH frequency resourceallocation” provided in RACH-ConfigDedicated IE or other resource blockassignment information element, where N_(RB) ^(UL,BWP) is the size ofthe initial or active UL BWP. According to another exemplary embodiment,the number of bits may be a fixed number (e.g., 12 bits or othersuitable number of bits).

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be based at least in part on commonsignaling (e.g., useInterlacePUSCH-Common, etc.) from the network node.The common signaling may indicate whether to enable interlaced resourceallocation for the uplink shared channel transmission.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be performed by the terminal device based atleast in part on one or more of:

-   -   first configuration information, which may be related to a        interlace configuration for uplink shared channel transmission        of the terminal device in a two-step CBRA procedure; and    -   second configuration information, which may be related to a        interlace configuration for uplink shared channel transmission        of the terminal device with configured grant based scheduling.

According to an exemplary embodiment, the first configurationinformation may indicate which interlace configuration of msgA PUSCH forCBRA may be selected for msgA PUSCH in the two-step CFRA procedure.Alternatively or additionally, the first configuration information mayindicate which PO configured for msgA PUSCH in CBRA may be selected formsgA PUSCH in the two-step CFRA procedure.

According to an exemplary embodiment, the second configurationinformation may comprise one or more parameters for the case ofconfigured UL grant Type 1, e.g., the parameteruseInterlacePUSCH-Dedicated used for configured grant type 1 PUSCHtransmission, and/or the parameter “frequency domain resourceallocation”, etc.

According to an exemplary embodiment, the first configurationinformation may be indicated by RRC signaling and/or other higher layersignaling from the network node. According to another exemplaryembodiment, the first configuration information may be predetermined. Inthis case, the terminal device may determine the interlace configurationfor uplink shared channel transmission according to the predeterminedinterlace configuration indicated by the first configurationinformation.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be performed by the terminal device based atleast in part on one or more of the following messages from the networknode: a handover command message, a beam failure recover message, and adownlink control channel order (e.g., a PDCCH order) for the two-stepCFRA procedure.

FIG. 4 is a flowchart illustrating a method 400 according to someembodiments of the present disclosure. The method 400 illustrated inFIG. 4 may be performed by a network node or an apparatuscommunicatively coupled to the network node. In accordance with anexemplary embodiment, the network node may comprise a base station suchas a gNB. The network node may be configured to communicate with one ormore terminal devices such as UEs which can connect to the network nodeby performing a RA procedure (e.g., a two-step CFRA procedure).

According to the exemplary method 400 illustrated in FIG. 4 , thenetwork node may determine a interlace configuration for uplink sharedchannel transmission of a terminal device (e.g., the terminal device asdescribed with respect to FIG. 3 ) in a two-step CFRA procedure, asshown in block 402. According to the determined interlace configuration,the network node may receive the uplink shared channel transmission fromthe terminal device in the two-step CFRA procedure, as shown in block404.

It can be appreciated that the steps, operations and relatedconfigurations of the method 400 illustrated in FIG. 4 may correspond tothe steps, operations and related configurations of the method 300illustrated in FIG. 3 . It also can be appreciated that the interlaceconfiguration for uplink shared channel transmission as described withrespect to FIG. 4 may correspond to the interlace configuration foruplink shared channel transmission as described with respect to FIG. 3 .Thus, the interlace configuration determined by the terminal device asdescribed with respect to the method 300 may have the same or similarcontents and feature elements as the interlace configuration determinedby the network node as described with respect to the method 400.

In accordance with some exemplary embodiments, the network node maytransmit dedicated signaling (e.g., the dedicated signaling as describedwith respect to FIG. 3 ) to the terminal device to indicate thedetermined interlace configuration.

In accordance with some exemplary embodiments, the network node maytransmit common signaling (e.g., the common signaling as described withrespect to FIG. 3 ) to the terminal device to indicate whether to enableinterlaced resource allocation for the uplink shared channeltransmission.

In accordance with some exemplary embodiments, the determination of theinterlace configuration may be performed by the network node based atleast in part on first configuration information (e.g., the firstconfiguration information as described with respect to FIG. 3 ), secondconfiguration information (e.g., the second configuration information asdescribed with respect to FIG. 3 ), and/or any other relatedinformation.

In accordance with some exemplary embodiments, the network node maytransmit higher layer signaling (e.g., RRC signaling, etc.) to theterminal device to indicate the first configuration information. It canbe appreciated that the first configuration information may bepredetermined. In this case, the network node may not inform theterminal device of the first configuration information.

In accordance with some exemplary embodiments, the network node mayindicate the determined interlace configuration to the terminal devicein one or more of the following messages: a handover command message, abeam failure recover message, and a downlink control channel order(e.g., a PDCCH order, etc.) for the two-step CFRA procedure.

Various exemplary embodiments according to the present disclosure mayenable interlaced resource allocation to be configured for msgA PUSCH ina two-step CFRA procedure. In accordance with some exemplaryembodiments, a terminal device may determine the interlaced msgA PUSCHconfiguration in CFRA according to some flexible signaling which may bedynamically provided in a dedicated message from a network node.Alternatively or additionally, in order to reduce the signalingoverhead, the interlaced msgA PUSCH configuration in CFRA may beimplemented via reusing some of the existing parameters and/or signalingfor interlace configuration. Application of various exemplaryembodiments can improve configuration flexibility of interlaced msgAPUSCH in CFRA and enhance performance of a two-step CFRA procedure.

The various blocks shown in FIGS. 3-4 may be viewed as method steps,and/or as operations that result from operation of computer programcode, and/or as a plurality of coupled logic circuit elementsconstructed to carry out the associated function(s). The schematic flowchart diagrams described above are generally set forth as logical flowchart diagrams. As such, the depicted order and labeled steps areindicative of specific embodiments of the presented methods. Other stepsand methods may be conceived that are equivalent in function, logic, oreffect to one or more steps, or portions thereof, of the illustratedmethods. Additionally, the order in which a particular method occurs mayor may not strictly adhere to the order of the corresponding stepsshown.

FIG. 5 is a block diagram illustrating an apparatus 500 according tovarious embodiments of the present disclosure. As shown in FIG. 5 , theapparatus 500 may comprise one or more processors such as processor 501and one or more memories such as memory 502 storing computer programcodes 503. The memory 502 may be non-transitorymachine/processor/computer readable storage medium. In accordance withsome exemplary embodiments, the apparatus 500 may be implemented as anintegrated circuit chip or module that can be plugged or installed intoa terminal device as described with respect to FIG. 3 , or a networknode as described with respect to FIG. 4 . In such case, the apparatus500 may be implemented as a terminal device as described with respect toFIG. 3 , or a network node as described with respect to FIG. 4 .

In some implementations, the one or more memories 502 and the computerprogram codes 503 may be configured to, with the one or more processors501, cause the apparatus 500 at least to perform any operation of themethod as described in connection with FIG. 3 . In otherimplementations, the one or more memories 502 and the computer programcodes 503 may be configured to, with the one or more processors 501,cause the apparatus 500 at least to perform any operation of the methodas described in connection with FIG. 4 . Alternatively or additionally,the one or more memories 502 and the computer program codes 503 may beconfigured to, with the one or more processors 501, cause the apparatus500 at least to perform more or less operations to implement theproposed methods according to the exemplary embodiments of the presentdisclosure.

FIG. 6A is a block diagram illustrating an apparatus 610 according tosome embodiments of the present disclosure. As shown in FIG. 6A, theapparatus 610 may comprise a determining unit 611 and a performing unit612. In an exemplary embodiment, the apparatus 610 may be implemented ina terminal device such as a UE. The determining unit 611 may be operableto carry out the operation in block 302, and the performing unit 612 maybe operable to carry out the operation in block 304. In an exemplaryembodiment, the performing unit 612 may be implemented as a transmittingunit to carry out the operation in block 304. Optionally, thedetermining unit 611 and/or the performing unit 612 may be operable tocarry out more or less operations to implement the proposed methodsaccording to the exemplary embodiments of the present disclosure.

FIG. 6B is a block diagram illustrating an apparatus 620 according tosome embodiments of the present disclosure. As shown in FIG. 6B, theapparatus 620 may comprise a determining unit 621 and a receiving unit622. In an exemplary embodiment, the apparatus 620 may be implemented ina network node such as a base station. The determining unit 621 may beoperable to carry out the operation in block 402, and the receiving unit622 may be operable to carry out the operation in block 404. Optionally,the determining unit 621 and/or the receiving unit 622 may be operableto carry out more or less operations to implement the proposed methodsaccording to the exemplary embodiments of the present disclosure.

FIG. 7 is a block diagram illustrating a telecommunication networkconnected via an intermediate network to a host computer in accordancewith some embodiments of the present disclosure.

With reference to FIG. 7 , in accordance with an embodiment, acommunication system includes a telecommunication network 710, such as a3GPP-type cellular network, which comprises an access network 711, suchas a radio access network, and a core network 714. The access network711 comprises a plurality of base stations 712 a, 712 b, 712 c, such asNBs, eNBs, gNBs or other types of wireless access points, each defininga corresponding coverage area 713 a, 713 b, 713 c. Each base station 712a, 712 b, 712 c is connectable to the core network 714 over a wired orwireless connection 715. A first UE 791 located in a coverage area 713 cis configured to wirelessly connect to, or be paged by, thecorresponding base station 712 c. A second UE 792 in a coverage area 713a is wirelessly connectable to the corresponding base station 712 a.While a plurality of UEs 791, 792 are illustrated in this example, thedisclosed embodiments are equally applicable to a situation where a soleUE is in the coverage area or where a sole UE is connecting to thecorresponding base station 712.

The telecommunication network 710 is itself connected to a host computer730, which may be embodied in the hardware and/or software of astandalone server, a cloud-implemented server, a distributed server oras processing resources in a server farm. The host computer 730 may beunder the ownership or control of a service provider, or may be operatedby the service provider or on behalf of the service provider.Connections 721 and 722 between the telecommunication network 710 andthe host computer 730 may extend directly from the core network 714 tothe host computer 730 or may go via an optional intermediate network720. An intermediate network 720 may be one of, or a combination of morethan one of, a public, private or hosted network; the intermediatenetwork 720, if any, may be a backbone network or the Internet; inparticular, the intermediate network 720 may comprise two or moresub-networks (not shown).

The communication system of FIG. 7 as a whole enables connectivitybetween the connected UEs 791, 792 and the host computer 730. Theconnectivity may be described as an over-the-top (OTT) connection 750.The host computer 730 and the connected UEs 791, 792 are configured tocommunicate data and/or signaling via the OTT connection 750, using theaccess network 711, the core network 714, any intermediate network 720and possible further infrastructure (not shown) as intermediaries. TheOTT connection 750 may be transparent in the sense that theparticipating communication devices through which the OTT connection 750passes are unaware of routing of uplink and downlink communications. Forexample, the base station 712 may not or need not be informed about thepast routing of an incoming downlink communication with data originatingfrom the host computer 730 to be forwarded (e.g., handed over) to aconnected UE 791. Similarly, the base station 712 need not be aware ofthe future routing of an outgoing uplink communication originating fromthe UE 791 towards the host computer 730.

FIG. 8 is a block diagram illustrating a host computer communicating viaa base station with a UE over a partially wireless connection inaccordance with some embodiments of the present disclosure.

Example implementations, in accordance with an embodiment, of the UE,base station and host computer discussed in the preceding paragraphswill now be described with reference to FIG. 8 . In a communicationsystem 800, a host computer 810 comprises hardware 815 including acommunication interface 816 configured to set up and maintain a wired orwireless connection with an interface of a different communicationdevice of the communication system 800. The host computer 810 furthercomprises a processing circuitry 818, which may have storage and/orprocessing capabilities. In particular, the processing circuitry 818 maycomprise one or more programmable processors, application-specificintegrated circuits, field programmable gate arrays or combinations ofthese (not shown) adapted to execute instructions. The host computer 810further comprises software 811, which is stored in or accessible by thehost computer 810 and executable by the processing circuitry 818. Thesoftware 811 includes a host application 812. The host application 812may be operable to provide a service to a remote user, such as UE 830connecting via an OTT connection 850 terminating at the UE 830 and thehost computer 810. In providing the service to the remote user, the hostapplication 812 may provide user data which is transmitted using the OTTconnection 850.

The communication system 800 further includes a base station 820provided in a telecommunication system and comprising hardware 825enabling it to communicate with the host computer 810 and with the UE830. The hardware 825 may include a communication interface 826 forsetting up and maintaining a wired or wireless connection with aninterface of a different communication device of the communicationsystem 800, as well as a radio interface 827 for setting up andmaintaining at least a wireless connection 870 with the UE 830 locatedin a coverage area (not shown in FIG. 8 ) served by the base station820. The communication interface 826 may be configured to facilitate aconnection 860 to the host computer 810. The connection 860 may bedirect or it may pass through a core network (not shown in FIG. 8 ) ofthe telecommunication system and/or through one or more intermediatenetworks outside the telecommunication system. In the embodiment shown,the hardware 825 of the base station 820 further includes a processingcircuitry 828, which may comprise one or more programmable processors,application-specific integrated circuits, field programmable gate arraysor combinations of these (not shown) adapted to execute instructions.The base station 820 further has software 821 stored internally oraccessible via an external connection.

The communication system 800 further includes the UE 830 alreadyreferred to. Its hardware 835 may include a radio interface 837configured to set up and maintain a wireless connection 870 with a basestation serving a coverage area in which the UE 830 is currentlylocated. The hardware 835 of the UE 830 further includes a processingcircuitry 838, which may comprise one or more programmable processors,application-specific integrated circuits, field programmable gate arraysor combinations of these (not shown) adapted to execute instructions.The UE 830 further comprises software 831, which is stored in oraccessible by the UE 830 and executable by the processing circuitry 838.The software 831 includes a client application 832. The clientapplication 832 may be operable to provide a service to a human ornon-human user via the UE 830, with the support of the host computer810. In the host computer 810, an executing host application 812 maycommunicate with the executing client application 832 via the OTTconnection 850 terminating at the UE 830 and the host computer 810. Inproviding the service to the user, the client application 832 mayreceive request data from the host application 812 and provide user datain response to the request data. The OTT connection 850 may transferboth the request data and the user data. The client application 832 mayinteract with the user to generate the user data that it provides.

It is noted that the host computer 810, the base station 820 and the UE830 illustrated in FIG. 8 may be similar or identical to the hostcomputer 730, one of base stations 712 a, 712 b, 712 c and one of UEs791, 792 of FIG. 7 , respectively. This is to say, the inner workings ofthese entities may be as shown in FIG. 8 and independently, thesurrounding network topology may be that of FIG. 7 .

In FIG. 8 , the OTT connection 850 has been drawn abstractly toillustrate the communication between the host computer 810 and the UE830 via the base station 820, without explicit reference to anyintermediary devices and the precise routing of messages via thesedevices. Network infrastructure may determine the routing, which it maybe configured to hide from the UE 830 or from the service provideroperating the host computer 810, or both. While the OTT connection 850is active, the network infrastructure may further take decisions bywhich it dynamically changes the routing (e.g., on the basis of loadbalancing consideration or reconfiguration of the network).

Wireless connection 870 between the UE 830 and the base station 820 isin accordance with the teachings of the embodiments described throughoutthis disclosure. One or more of the various embodiments improve theperformance of OTT services provided to the UE 830 using the OTTconnection 850, in which the wireless connection 870 forms the lastsegment. More precisely, the teachings of these embodiments may improvethe latency and the power consumption, and thereby provide benefits suchas lower complexity, reduced time required to access a cell, betterresponsiveness, extended battery lifetime, etc.

A measurement procedure may be provided for the purpose of monitoringdata rate, latency and other factors on which the one or moreembodiments improve. There may further be an optional networkfunctionality for reconfiguring the OTT connection 850 between the hostcomputer 810 and the UE 830, in response to variations in themeasurement results. The measurement procedure and/or the networkfunctionality for reconfiguring the OTT connection 850 may beimplemented in software 811 and hardware 815 of the host computer 810 orin software 831 and hardware 835 of the UE 830, or both. In embodiments,sensors (not shown) may be deployed in or in association withcommunication devices through which the OTT connection 850 passes; thesensors may participate in the measurement procedure by supplying valuesof the monitored quantities exemplified above, or supplying values ofother physical quantities from which the software 811, 831 may computeor estimate the monitored quantities. The reconfiguring of the OTTconnection 850 may include message format, retransmission settings,preferred routing etc.; the reconfiguring need not affect the basestation 820, and it may be unknown or imperceptible to the base station820. Such procedures and functionalities may be known and practiced inthe art. In certain embodiments, measurements may involve proprietary UEsignaling facilitating the host computer 810's measurements ofthroughput, propagation times, latency and the like. The measurementsmay be implemented in that the software 811 and 831 causes messages tobe transmitted, in particular empty or ‘dummy’ messages, using the OTTconnection 850 while it monitors propagation times, errors etc.

FIG. 9 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 7 and FIG. 8 . Forsimplicity of the present disclosure, only drawing references to FIG. 9will be included in this section. In step 910, the host computerprovides user data. In substep 911 (which may be optional) of step 910,the host computer provides the user data by executing a hostapplication. In step 920, the host computer initiates a transmissioncarrying the user data to the UE. In step 930 (which may be optional),the base station transmits to the UE the user data which was carried inthe transmission that the host computer initiated, in accordance withthe teachings of the embodiments described throughout this disclosure.In step 940 (which may also be optional), the UE executes a clientapplication associated with the host application executed by the hostcomputer.

FIG. 10 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 7 and FIG. 8 . Forsimplicity of the present disclosure, only drawing references to FIG. 10will be included in this section. In step 1010 of the method, the hostcomputer provides user data. In an optional substep (not shown) the hostcomputer provides the user data by executing a host application. In step1020, the host computer initiates a transmission carrying the user datato the UE. The transmission may pass via the base station, in accordancewith the teachings of the embodiments described throughout thisdisclosure. In step 1030 (which may be optional), the UE receives theuser data carried in the transmission.

FIG. 11 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 7 and FIG. 8 . Forsimplicity of the present disclosure, only drawing references to FIG. 11will be included in this section. In step 1110 (which may be optional),the UE receives input data provided by the host computer. Additionallyor alternatively, in step 1120, the UE provides user data. In substep1121 (which may be optional) of step 1120, the UE provides the user databy executing a client application. In substep 1111 (which may beoptional) of step 1110, the UE executes a client application whichprovides the user data in reaction to the received input data providedby the host computer. In providing the user data, the executed clientapplication may further consider user input received from the user.Regardless of the specific manner in which the user data was provided,the UE initiates, in substep 1130 (which may be optional), transmissionof the user data to the host computer. In step 1140 of the method, thehost computer receives the user data transmitted from the UE, inaccordance with the teachings of the embodiments described throughoutthis disclosure.

FIG. 12 is a flowchart illustrating a method implemented in acommunication system, in accordance with an embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIG. 7 and FIG. 8 . Forsimplicity of the present disclosure, only drawing references to FIG. 12will be included in this section. In step 1210 (which may be optional),in accordance with the teachings of the embodiments described throughoutthis disclosure, the base station receives user data from the UE. Instep 1220 (which may be optional), the base station initiatestransmission of the received user data to the host computer. In step1230 (which may be optional), the host computer receives the user datacarried in the transmission initiated by the base station.

According to some exemplary embodiments, there is provided a methodimplemented in a communication system which may include a host computer,a base station and a UE. The method may comprise providing user data atthe host computer. Optionally, the method may comprise, at the hostcomputer, initiating a transmission carrying the user data to the UE viaa cellular network comprising the base station which may perform anystep of the exemplary method 400 as describe with respect to FIG. 4 .

According to some exemplary embodiments, there is provided acommunication system including a host computer. The host computer maycomprise processing circuitry configured to provide user data, and acommunication interface configured to forward the user data to acellular network for transmission to a UE. The cellular network maycomprise a base station having a radio interface and processingcircuitry. The base station's processing circuitry may be configured toperform any step of the exemplary method 400 as describe with respect toFIG. 4 .

According to some exemplary embodiments, there is provided a methodimplemented in a communication system which may include a host computer,a base station and a UE. The method may comprise providing user data atthe host computer. Optionally, the method may comprise, at the hostcomputer, initiating a transmission carrying the user data to the UE viaa cellular network comprising the base station. The UE may perform anystep of the exemplary method 300 as describe with respect to FIG. 3 .

According to some exemplary embodiments, there is provided acommunication system including a host computer. The host computer maycomprise processing circuitry configured to provide user data, and acommunication interface configured to forward user data to a cellularnetwork for transmission to a UE. The UE may comprise a radio interfaceand processing circuitry. The UE's processing circuitry may beconfigured to perform any step of the exemplary method 300 as describewith respect to FIG. 3 .

According to some exemplary embodiments, there is provided a methodimplemented in a communication system which may include a host computer,a base station and a UE. The method may comprise, at the host computer,receiving user data transmitted to the base station from the UE whichmay perform any step of the exemplary method 300 as describe withrespect to FIG. 3 .

According to some exemplary embodiments, there is provided acommunication system including a host computer. The host computer maycomprise a communication interface configured to receive user dataoriginating from a transmission from a UE to a base station. The UE maycomprise a radio interface and processing circuitry. The UE's processingcircuitry may be configured to perform any step of the exemplary method300 as describe with respect to FIG. 3 .

According to some exemplary embodiments, there is provided a methodimplemented in a communication system which may include a host computer,a base station and a UE. The method may comprise, at the host computer,receiving, from the base station, user data originating from atransmission which the base station has received from the UE. The basestation may perform any step of the exemplary method 400 as describewith respect to FIG. 4 .

According to some exemplary embodiments, there is provided acommunication system which may include a host computer. The hostcomputer may comprise a communication interface configured to receiveuser data originating from a transmission from a UE to a base station.The base station may comprise a radio interface and processingcircuitry. The base station's processing circuitry may be configured toperform any step of the exemplary method 400 as describe with respect toFIG. 4 .

In general, the various exemplary embodiments may be implemented inhardware or special purpose chips, circuits, software, logic or anycombination thereof. For example, some aspects may be implemented inhardware, while other aspects may be implemented in firmware or softwarewhich may be executed by a controller, microprocessor or other computingdevice, although the disclosure is not limited thereto. While variousaspects of the exemplary embodiments of this disclosure may beillustrated and described as block diagrams, flow charts, or using someother pictorial representation, it is well understood that these blocks,apparatus, systems, techniques or methods described herein may beimplemented in, as non-limiting examples, hardware, software, firmware,special purpose circuits or logic, general purpose hardware orcontroller or other computing devices, or some combination thereof.

As such, it should be appreciated that at least some aspects of theexemplary embodiments of the disclosure may be practiced in variouscomponents such as integrated circuit chips and modules. It should thusbe appreciated that the exemplary embodiments of this disclosure may berealized in an apparatus that is embodied as an integrated circuit,where the integrated circuit may comprise circuitry (as well as possiblyfirmware) for embodying at least one or more of a data processor, adigital signal processor, baseband circuitry and radio frequencycircuitry that are configurable so as to operate in accordance with theexemplary embodiments of this disclosure.

It should be appreciated that at least some aspects of the exemplaryembodiments of the disclosure may be embodied in computer-executableinstructions, such as in one or more program modules, executed by one ormore computers or other devices. Generally, program modules includeroutines, programs, objects, components, data structures, etc. thatperform particular tasks or implement particular abstract data typeswhen executed by a processor in a computer or other device. The computerexecutable instructions may be stored on a computer readable medium suchas a hard disk, optical disk, removable storage media, solid statememory, random access memory (RAM), etc. As will be appreciated by oneof skill in the art, the function of the program modules may be combinedor distributed as desired in various embodiments. In addition, thefunction may be embodied in whole or partly in firmware or hardwareequivalents such as integrated circuits, field programmable gate arrays(FPGA), and the like.

The present disclosure includes any novel feature or combination offeatures disclosed herein either explicitly or any generalizationthereof. Various modifications and adaptations to the foregoingexemplary embodiments of this disclosure may become apparent to thoseskilled in the relevant arts in view of the foregoing description, whenread in conjunction with the accompanying drawings. However, any and allmodifications will still fall within the scope of the non-limiting andexemplary embodiments of this disclosure.

1. A method performed by a terminal device, comprising: determining aninterlace configuration for uplink shared channel transmission to anetwork node in a two-step contention-free random access procedure; andperforming the uplink shared channel transmission to the network node inthe two-step contention-free random access procedure, according to thedetermined interlace configuration; wherein the determination of theinterlace configuration is based at least in part on dedicated signalingfor the two-step contention-free random access procedure from thenetwork node; wherein the dedicated signaling includes: a startinterlace index for an interlace; and a number of consecutive interlacesallocated for the uplink shared channel transmission.
 2. The methodaccording to claim 1, wherein the determination of the interlaceconfiguration is based at least in part on common signaling from thenetwork node, and the common signaling indicates whether to enableinterlaced resource allocation for the uplink shared channeltransmission.
 3. The method according to claim 1, wherein thedetermination of the interlace configuration is based at least in parton one or more of: first configuration information, which is related toa interlace configuration for uplink shared channel transmission of theterminal device in a two-step contention-based random access procedure;and second configuration information, which is related to an interlaceconfiguration for uplink shared channel transmission of the terminaldevice with configured grant based scheduling.
 4. The method accordingto claim 3, wherein the first configuration information is indicated byradio resource control signaling from the network node.
 5. The methodaccording to claim 4, wherein the first configuration information ispredetermined.
 6. The method according to claim 1, wherein thedetermination of the interlace configuration is based at least in parton one or more of the following messages from the network node: ahandover command message; a beam failure recover message; and a downlinkcontrol channel order for the two-step contention-free random accessprocedure.
 7. A method performed by a network node, comprising:determining an interlace configuration for uplink shared channeltransmission of a terminal device in a two-step contention-free randomaccess procedure; and receiving the uplink shared channel transmissionfrom the terminal device in the two-step contention-free random accessprocedure, according to the determined interlace configuration;transmitting dedicated signaling to the terminal device to indicate thedetermined interlace configuration; wherein the dedicated signalingincludes: a start interlace index for an interlace; and a number ofconsecutive interlaces allocated for the uplink shared channeltransmission.
 8. The method according to claim 7, further comprising:transmitting common signaling to the terminal device to indicate whetherto enable interlaced resource allocation for the uplink shared channeltransmission.
 9. The method according to claim 8, wherein thedetermination of the interlace configuration is based at least in parton one or more of: first configuration information, which is related toan interlace configuration for uplink shared channel transmission of theterminal device in a two-step contention-based random access procedure;and second configuration information, which is related to a interlaceconfiguration for uplink shared channel transmission of the terminaldevice with configured grant based scheduling.
 10. The method accordingto claim 8, further comprising: transmitting radio resource controlsignaling to the terminal device to indicate the first configurationinformation.
 11. The method according to claim 10, wherein the firstconfiguration information is predetermined.
 12. The method according toclaim 11, further comprising indicating the determined interlaceconfiguration to the terminal device in one or more of the followingmessages: a handover command message; a beam failure recover message;and a downlink control channel order for the two-step contention-freerandom access procedure.
 13. A terminal device, comprising: one or moreprocessors; and one or more memories comprising computer program codes,the one or more memories and the computer program codes configured to,with the one or more processors, cause the terminal device at least to:determine an interlace configuration for uplink shared channeltransmission to a network node in a two-step contention-free randomaccess procedure; and perform the uplink shared channel transmission tothe network node in the two-step contention-free random accessprocedure, according to the determined interlace configuration; whereinthe determination of the interlace configuration is based at least inpart on dedicated signaling for the two-step contention-free randomaccess procedure from the network node; wherein the dedicated signalingincludes one or more of: a start interlace index for an interlace; and anumber of consecutive interlaces allocated for the uplink shared channeltransmission.
 14. The terminal device according to claim 13, wherein thedetermination of the interlace configuration is based at least in parton common signaling from the network node, and the common signalingindicates whether to enable interlaced resource allocation for theuplink shared channel transmission.
 15. The terminal device according toclaim 13, wherein the determination of the interlace configuration isbased at least in part on one or more of: first configurationinformation, which is related to an interlace configuration for uplinkshared channel transmission of the terminal device in a two-stepcontention-based random access procedure; and second configurationinformation, which is related to a interlace configuration for uplinkshared channel transmission of the terminal device with configured grantbased scheduling.
 16. The terminal device according to claim 15, whereinthe first configuration is indicated by radio resource control signalingfrom the network node.
 17. The terminal device according to claim 16,wherein the first configuration information is predetermined.
 18. Theterminal device according to claim 17, wherein the determination of theinterlace configuration is based at least in part on one or more of thefollowing messages from the network node: a handover command message; abeam failure recover message; and a downlink control channel order forthe two-step contention-free random access procedure.
 19. The methodaccording to claim 13, wherein the dedicated signaling includes aspecific field with a number of bits to indicate frequency resourceallocation for the uplink shared channel transmission in the two-stepcontention-free random access procedure.
 20. The method according toclaim 14, wherein the number of bits is related to a size of an activeuplink bandwidth part.